How to pronounce "astronauts"

I have a question:

Who here remembers when they first realized

they were going to die?

I do. I was a young boy,

and my grandfather had just died,

and I remember a few days later lying in bed at night

trying to make sense of what had happened.

What did it mean that he was dead?

Where had he gone?

It was like a hole in reality had opened up

and swallowed him.

But then the really shocking question occurred to me:

If he could die, could it happen to me too?

Could that hole in reality open up and swallow me?

Would it open up beneath my bed

and swallow me as I slept?

Well, at some point, all children become aware of death.

It can happen in different ways, of course,

and usually comes in stages.

Our idea of death develops as we grow older.

And if you reach back into the dark corners

of your memory,

you might remember something like what I felt

when my grandfather died and when I realized

it could happen to me too,

that sense that behind all of this

the void is waiting.

And this development in childhood

reflects the development of our species.

Just as there was a point in your development

as a child when your sense of self and of time

became sophisticated enough

for you to realize you were mortal,

so at some point in the evolution of our species,

some early human's sense of self and of time

became sophisticated enough

for them to become the first human to realize,

"I'm going to die."

This is, if you like, our curse.

It's the price we pay for being so damn clever.

We have to live in the knowledge

that the worst thing that can possibly happen

one day surely will,

the end of all our projects,

our hopes, our dreams, of our individual world.

We each live in the shadow of a personal

apocalypse.

And that's frightening. It's terrifying.

And so we look for a way out.

And in my case, as I was about five years old,

this meant asking my mum.

Now when I first started asking

what happens when we die,

the grown-ups around me at the time

answered with a typical English mix of awkwardness

and half-hearted Christianity,

and the phrase I heard most often

was that granddad was now

"up there looking down on us,"

and if I should die too, which wouldn't happen of course,

then I too would go up there,

which made death sound a lot like

an existential elevator.

Now this didn't sound very plausible.

I used to watch a children's news program at the time,

and this was the era of space exploration.

There were always rockets going up into the sky,

up into space, going up there.

But none of the astronauts when they came back

ever mentioned having met my granddad

or any other dead people.

But I was scared,

and the idea of taking the existential elevator

to see my granddad

sounded a lot better than being swallowed

by the void while I slept.

And so I believed it anyway,

even though it didn't make much sense.

And this thought process that I went through

as a child, and have been through many times since,

including as a grown-up,

is a product of what psychologists call

a bias.

Now a bias is a way in which we systematically

get things wrong,

ways in which we miscalculate, misjudge,

distort reality, or see what we want to see,

and the bias I'm talking about

works like this:

Confront someone with the fact

that they are going to die

and they will believe just about any story

that tells them it isn't true

and they can, instead, live forever,

even if it means taking the existential elevator.

Now we can see this as the biggest bias of all.

It has been demonstrated in over 400

empirical studies.

Now these studies are ingenious, but they're simple.

They work like this.

You take two groups of people

who are similar in all relevant respects,

and you remind one group that they're going to die

but not the other, then you compare their behavior.

So you're observing how it biases behavior

when people become aware of their mortality.

And every time, you get the same result:

People who are made aware of their mortality

are more willing to believe stories

that tell them they can escape death

and live forever.

So here's an example: One recent study

took two groups of agnostics,

that is people who are undecided

in their religious beliefs.

Now, one group was asked to think about being dead.

The other group was asked to think about

being lonely.

They were then asked again about their religious beliefs.

Those who had been asked to think about being dead

were afterwards twice as likely to express faith

in God and Jesus.

Twice as likely.

Even though the before they were all equally agnostic.

But put the fear of death in them,

and they run to Jesus.

Now, this shows that reminding people of death

biases them to believe, regardless of the evidence,

and it works not just for religion,

but for any kind of belief system

that promises immortality in some form,

whether it's becoming famous

or having children

or even nationalism,

which promises you can live on as part of a greater whole.

This is a bias that has shaped

the course of human history.

Now, the theory behind this bias

in the over 400 studies

is called terror management theory,

and the idea is simple. It's just this.

We develop our worldviews,

that is, the stories we tell ourselves

about the world and our place in it,

in order to help us manage

the terror of death.

And these immortality stories

have thousands of different manifestations,

but I believe that behind the apparent diversity

there are actually just four basic forms

that these immortality stories can take.

And we can see them repeating themselves

throughout history, just with slight variations

to reflect the vocabulary of the day.

Now I'm going to briefly introduce these four

basic forms of immortality story,

and I want to try to give you some sense

of the way in which they're retold by each culture

or generation

using the vocabulary of their day.

Now, the first story is the simplest.

We want to avoid death,

and the dream of doing that in this body

in this world forever

is the first and simplest kind of immortality story,

and it might at first sound implausible,

but actually, almost every culture in human history

has had some myth or legend

of an elixir of life or a fountain of youth

or something that promises to keep us going

forever.

Ancient Egypt had such myths,

ancient Babylon, ancient India.

Throughout European history, we find them in the work of the alchemists,

and of course we still believe this today,

only we tell this story using the vocabulary

of science.

So 100 years ago,

hormones had just been discovered,

and people hoped that hormone treatments

were going to cure aging and disease,

and now instead we set our hopes on stem cells,

genetic engineering, and nanotechnology.

But the idea that science can cure death

is just one more chapter in the story

of the magical elixir,

a story that is as old as civilization.

But betting everything on the idea of finding the elixir

and staying alive forever

is a risky strategy.

When we look back through history

at all those who have sought an elixir in the past,

the one thing they now have in common

is that they're all dead.

So we need a backup plan, and exactly this kind of plan B

is what the second kind of immortality story offers,

and that's resurrection.

And it stays with the idea that I am this body,

I am this physical organism.

It accepts that I'm going to have to die

but says, despite that,

I can rise up and I can live again.

In other words, I can do what Jesus did.

Jesus died, he was three days in the [tomb],

and then he rose up and lived again.

And the idea that we can all be resurrected to live again

is orthodox believe, not just for Christians

but also Jews and Muslims.

But our desire to believe this story

is so deeply embedded

that we are reinventing it again

for the scientific age,

for example, with the idea of cryonics.

That's the idea that when you die,

you can have yourself frozen,

and then, at some point when technology

has advanced enough,

you can be thawed out and repaired and revived

and so resurrected.

And so some people believe an omnipotent god

will resurrect them to live again,

and other people believe an omnipotent scientist will do it.

But for others, the whole idea of resurrection,

of climbing out of the grave,

it's just too much like a bad zombie movie.

They find the body too messy, too unreliable

to guarantee eternal life,

and so they set their hopes on the third,

more spiritual immortality story,

the idea that we can leave our body behind

and live on as a soul.

Now, the majority of people on Earth

believe they have a soul,

and the idea is central to many religions.

But even though, in its current form,

in its traditional form,

the idea of the soul is still hugely popular,

nonetheless we are again

reinventing it for the digital age,

for example with the idea

that you can leave your body behind

by uploading your mind, your essence,

the real you, onto a computer,

and so live on as an avatar in the ether.

But of course there are skeptics who say

if we look at the evidence of science,

particularly neuroscience,

it suggests that your mind,

your essence, the real you,

is very much dependent on a particular part

of your body, that is, your brain.

And such skeptics can find comfort

in the fourth kind of immortality story,

and that is legacy,

the idea that you can live on

through the echo you leave in the world,

like the great Greek warrior Achilles,

who sacrificed his life fighting at Troy

so that he might win immortal fame.

And the pursuit of fame is as widespread

and popular now as it ever was,

and in our digital age,

it's even easier to achieve.

You don't need to be a great warrior like Achilles

or a great king or hero.

All you need is an Internet connection and a funny cat. (Laughter)

But some people prefer to leave a more tangible,

biological legacy -- children, for example.

Or they like, they hope, to live on

as part of some greater whole,

a nation or a family or a tribe,

their gene pool.

But again, there are skeptics

who doubt whether legacy

really is immortality.

Woody Allen, for example, who said,

"I don't want to live on in the hearts of my countrymen.

I want to live on in my apartment."

So those are the four

basic kinds of immortality stories,

and I've tried to give just some sense

of how they're retold by each generation

with just slight variations

to fit the fashions of the day.

And the fact that they recur in this way,

in such a similar form but in such different belief systems,

suggests, I think,

that we should be skeptical of the truth

of any particular version of these stories.

The fact that some people believe

an omnipotent god will resurrect them to live again

and others believe an omnipotent scientist will do it

suggests that neither are really believing this

on the strength of the evidence.

Rather, we believe these stories

because we are biased to believe them,

and we are biased to believe them

because we are so afraid of death.

So the question is,

are we doomed to lead the one life we have

in a way that is shaped by fear and denial,

or can we overcome this bias?

Well the Greek philosopher Epicurus

thought we could.

He argued that the fear of death is natural,

but it is not rational.

"Death," he said, "is nothing to us,

because when we are here, death is not,

and when death is here, we are gone."

Now this is often quoted, but it's difficult

to really grasp, to really internalize,

because exactly this idea of being gone

is so difficult to imagine.

So 2,000 years later, another philosopher,

Ludwig Wittgenstein, put it like this:

"Death is not an event in life:

We do not live to experience death.

And so," he added,

"in this sense, life has no end."

So it was natural for me as a child

to fear being swallowed by the void,

but it wasn't rational,

because being swallowed by the void

is not something that any of us

will ever live to experience.

Now, overcoming this bias is not easy because

the fear of death is so deeply embedded in us,

yet when we see that the fear itself is not rational,

and when we bring out into the open

the ways in which it can unconsciously bias us,

then we can at least start

to try to minimize the influence it has

on our lives.

Now, I find it helps to see life

as being like a book:

Just as a book is bounded by its covers,

by beginning and end,

so our lives are bounded by birth and death,

and even though a book is limited by beginning and end,

it can encompass distant landscapes,

exotic figures, fantastic adventures.

And even though a book is limited by beginning and end,

the characters within it

know no horizons.

They only know the moments that make up their story,

even when the book is closed.

And so the characters of a book

are not afraid of reaching the last page.

Long John Silver is not afraid of you

finishing your copy of "Treasure Island."

And so it should be with us.

Imagine the book of your life,

its covers, its beginning and end, and your birth and your death.

You can only know the moments in between,

the moments that make up your life.

It makes no sense for you to fear

what is outside of those covers,

whether before your birth

or after your death.

And you needn't worry how long the book is,

or whether it's a comic strip or an epic.

The only thing that matters

is that you make it a good story.

Thank you.

(Applause)